The invention relates to a cuvette for liquid or gaseous samples, particularly for absorption spectrum analysis, the cuvette comprising a multi-part housing structure which encloses a thin sample chamber that is delimited by two radiation transmitting discs and is provided with two bores leading to the sample chamber.
The bores serve as fill and ventilation channel for the sample chamber and, in prior art cuvettes of this type, are provided with a screwed-in connecting nipple which itself is provided with a precisely ground, hollow, conical connecting piece or a screw connection as is well known for the tight connection of injection needles with multi-use injection syringes. To fill the cuvette, the syringe containing the sample fluid is connected with the fill end and, if fluid escapes at the other end after filling of the sample chamber, the latter is closed by means of a stopper. Then the syringe is removed and the fill end is likewise closed.
The drawbacks here are that, compared to the small capacity of the sample chamber, a relatively large volume of sample fluid is required to fill the connecting nipples and that sample fluid is usually pressed out when the ends or nipples are sealed, which is annoying and makes work more difficult. On the other hand, air inclusions often remain in the channels.